This gene encodes a cell-surface anchored serine protease, which is a member of the trypsin family of serine proteases. It is predicted to be active on peptide linkages involving the carboxyl group of lysine or arginine. The protein localizes to the cytoplasm and the plasma membrane of premeiotic testicular germ cells and it may be involved in progression of testicular tumors of germ cell origin. Alternative splicing of this gene results in three transcript variants encoding three different isoforms. [provided by RefSeq].